Re: [PATCH 5/8] cfq-iosched: remove @gfp_mask from cfq_find_alloc_queue()

[Jeff Moyer <jmoyer-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>]

Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> writes:

> Hey, Jeff.
>
> On Mon, Jun 08, 2015 at 04:27:10PM -0400, Jeff Moyer wrote:
>> >> Remove @gfp_mask from cfq_find_alloc_queue() and propagate the changes
>> >> to its callers.  This simplifies the function quite a bit and will
>> >> help making async queues per-cfq_group.
>> >
>> > Sorry, I disagree with this patch.  You've changed it so that all cfqq
>> > allocations are GFP_ATOMIC, and most, if not all of them simply don't
>> > need to be.
>> 
>> It occurs to me that replacing GFP_ATOMIC with GFP_NOWAIT in your patch
>> would address my concerns, and patches 6-8 would apply almost as-is.
>> What do you think about that?
>
> Oh yeah, it's okay to fail these allocations under memory pressure.
> GFP_NOWAIT is the better pick here.  It's GFP_ATOMIC mostly due to
> historic copy&paste anyway.  I'll change them to GFP_NOWAIT.

OK.  Assuming that's the only change, you can go ahead and add my
Reviewed-by: Jeff Moyer <jmoyer-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> to the next iteration.

Thanks!
Jeff